U.S. patent number 5,087,247 [Application Number 07/574,370] was granted by the patent office on 1992-02-11 for balloon perfusion catheter.
This patent grant is currently assigned to Cardiovascular Designs, Inc.. Invention is credited to Joseph B. Horn, James F. King, Allen J. Tower.
United States Patent |
5,087,247 |
Horn , et al. |
February 11, 1992 |
Balloon perfusion catheter
Abstract
Balloon perfusion catheter having a flexible elongated shaft
from which a perfusion shaft and an inflation shaft outwardly
extend. An angioplasty balloon is circumferentially mounted around
the perfusion shaft. The inflation shaft distal end is located at
the balloon proximal end. Openings in the perfusion shaft both
proximal and distal to the balloon permit blood flow through artery
during balloon inflation.
Inventors: |
Horn; Joseph B. (Topsfield,
MA), Tower; Allen J. (North Lawrence, NY), King; James
F. (Wauwatosa, WI) |
Assignee: |
Cardiovascular Designs, Inc.
(Peabody, MA)
|
Family
ID: |
24295828 |
Appl.
No.: |
07/574,370 |
Filed: |
August 28, 1990 |
Current U.S.
Class: |
604/98.01;
604/103.1; 604/913; 606/192; 606/194 |
Current CPC
Class: |
A61M
25/104 (20130101); A61M 2025/1097 (20130101); A61M
2025/0177 (20130101) |
Current International
Class: |
A61M
29/02 (20060101); A61M 029/00 () |
Field of
Search: |
;128/207.15
;604/96-103,53 ;606/191-194 ;600/31,32 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Rosenbaum; C. Fred
Assistant Examiner: Smith; Chalin
Attorney, Agent or Firm: Corless; Peter F. Williams; Gregory
D.
Claims
We claim:
1. A dilation catheter, comprising:
(a) a flexible elongated shaft having a first lumen longitudinally
extending therewithin and a second lumen longitudinally extending
therewithin;
(b) a perfusion shaft outwardly extending from and in communication
with the first lumen;
(c) a balloon circumscribing the perfusion shaft, the perfusion
shaft having a plurality of openings proximal and distal to the
balloon; and
(d) an inflation shaft outwardly extending from and in
communication with the second lumen, the perfusion shaft for at
least a portion of its length being physically separate from the
inflation shaft.
2. A dilation catheter as recited in claim 1, wherein the plurality
of openings are offset to at least partially circumscribe the
perfusion shaft both proximal and distal to the balloon.
3. A dilation catheter as recited in claim 1, wherein the plurality
of openings spirally circumscribe the perfusion catheter both
proximal and distal to the balloon.
4. A dilation catheter as recited in claim 1, wherein the perfusion
shaft extends from the flexible elongated shaft separate from and
without attachment to the inflation shaft, and then attaches to the
inflation shaft at the inflation shaft distal end.
5. A dilation catheter as recited in claim 1, wherein the perfusion
shaft extends to the perfusion shaft distal end separate from and
without attachment to the inflation shaft for at least about 10
percent of the length of the perfusion shaft.
6. A dilation catheter as recited in claim 1, wherein the first
lumen and the perfusion shaft are adapted to receive a guide
wire.
7. A dilation catheter as recited in claim 1, wherein the second
lumen and the inflation shaft are adapted to receive fluid.
8. A dilation catheter as recited in claim 1, wherein a distal end
marker is affixed on the perfusion shaft near the perfusion shaft
distal end, a balloon marker is affixed on the perfusion shaft
beneath the balloon, and a proximal end marker is affixed on the
perfusion shaft near the perfusion shaft proximal end.
9. A dilation catheter as recited in claim 1, wherein there are
between about 4 to 40 openings proximal to the balloon and between
about 2 to 20 openings distal to the balloon.
10. A dilation catheter as recited in claim 1, wherein there are
between about 10 and 40 openings proximal to the balloon and
between about 4 and 10 openings distal to the balloon.
11. A dilation catheter as recited in claim 1, wherein there are
between about 20 to 30 openings proximal to the balloon and between
about 6 to 8 openings distal to the balloon.
12. A dilation catheter as recited in claim 1, wherein the
plurality of openings are round in shape.
13. A dilation catheter as recited in claim 1, wherein each opening
is between about 0.010 and 0.040 inches in diameter.
14. A dilation catheter as recited in claim 1, wherein each opening
is between about 0.014 nd 0.024 inches in diameter.
15. A dilation catheter as recited in claim 1, wherein each opening
is about 0.022 inches in diameter.
16. A dilation catheter as recited in claim 1, wherein the
inflation shaft communicates with the balloon at the inflation
shaft distal end and the balloon proximal end.
17. A dilation catheter as recited in claim 1, wherein the
plurality of openings circumscribe the perfusion shaft both
proximal and distal to the balloon.
Description
FIELD OF THE INVENTION
This invention relates to perfusion catheters and, more
particularly, to perfusion dilation catheters used for arterial
angioplasty.
BACKGROUND OF THE INVENTION
Catheters are commonly used invasively to treat cardiovascular
diseases through a method known as balloon angioplasty. A catheter
is employed having a balloon portion near the catheter's distal
end. The balloon portion is placed within an obstructed artery and
inflated; expanding outwardly, the balloon dilates the arterial
vessel.
Balloon angioplasty procedures when successful avoid bypass surgery
and the attendant costs and medical risks thereof. Effective
treatment of arterial stenoses, however, may not be realized
through current balloon angioplasty methods for a number of
reasons. For example, the lumen through the stenosis may be too
narrow to permit entry of the deflated balloon catheter. Also,
inflation times of currently used balloon catheters may be limited
to 15 to 60 seconds due to occlusion of the arterial opening by the
inflated balloon. This limited inflation time is often not
sufficient to treat the stenosis and inflations must be repeated.
Further, even if the arterial lumen is successfully dilated, the
effect may be only temporary. Restenosis of the artery after
treatment is not uncommon. It is believed, however, that a
sustained inflation of the catheter balloon, rather than shorter
multiple inflations, would reduce the possibility of such
post-treatment restenosis.
A sustained inflation period also permits use of relatively lower
inflation pressures. Extended, low pressure inflation tends to
compress, rather than tear, plague of an arterial lesion over time.
By not tearing the arterial lesion, healing of the dissection is
facilitated. In contrast, conventional shorter multiple balloon
inflations performed at relatively high inflation pressures could
tear the arterial lesion thereby prolonging recovery or entirely
preventing successful treatment.
SUMMARY OF THE INVENTION
The present invention comprises an improved balloon perfusion
catheter that provides many advantages not afforded by conventional
catheters. More specifically, the present invention provides a
perfusion balloon catheter having a flexible elongated shaft, which
shaft is provided with first and second lumens extending
therewithin. A perfusion shaft and inflation shaft extend outwardly
from, and are in communication with, the first and second lumens,
respectively. A portion of the perfusion shaft has an angioplasty
balloon mounted circumferentially therearound. The inflation shaft
distal end is located at the balloon proximal end and therefore the
inflation shaft does not enter the stenosis lumen during treatment.
As the perfusion shaft with circumscribing balloon is the largest
diameter portion of the catheter that need be inserted into an
arterial stenosis, lesions having relatively small openings can be
treated successfully.
Both proximal and distal to the balloon, the perfusion shaft has a
plurality of openings which permit blood flow through the artery
during balloon inflation thereby providing the advantage of longer
balloon inflation time. Preferably, the openings spirally
circumscribe the perfusion shaft both proximal and distal to the
balloon, each opening being radially offset from each adjacent
opening. Such spiral circumscription has been found to provide
enhanced blood flow into and through the perfusion shaft.
The inflation shaft generally extends from the elongated shaft to
the balloon at least partially separate from and without attachment
to the perfusion shaft. At least partial separation of the
perfusion shaft and inflation permits advantageous circumscription
of the perfusion shaft by the plurality of openings.
The perfusion shaft has a distal end radiopaque marker affixed
thereon near the perfusion shaft distal end, a balloon radiopaque
marker affixed thereon and beneath the balloon, and a proximal end
radiopaque marker affixed thereon near the perfusion shaft proximal
end. A guide wire may be inserted through the first lumen and the
perfusion shaft to provide means for advancing the balloon to the
targeted artery.
It is an object of the invention to provide a balloon dilation
catheter which permits an angioplasty procedure on a stenosis
lumen, including a narrow stenosis lumen.
It is another object of the invention to provide a balloon dilation
catheter which affords enhanced blood perfusion through an
obstructed artery during balloon inflation.
It is a further object of the invention to provide a balloon
dilation catheter which permits use of relatively long balloon
inflation times and low balloon inflation pressures.
BRIEF DESCRIPTION OF THE DRAWING
A more complete understanding of the invention may be provided by
reference to the accompanying drawing wherein:
FIG. 1 is a top view of the catheter of the present invention;
FIG. 2 is an enlarged top view of a distal portion of the catheter
of the present invention;
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG.
2;
FIG. 4 is a cross sectional view taken along the line 4--4 of FIG.
1.; and
FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG.
2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention as shown in FIGS. 1-5 provides a catheter 10
having a flexible elongated shaft 12 with first lumen 14
longitudinally extending therewithin and second lumen 6
longitudinally extending therewithin. Perfusion shaft 18 extends
outwardly from, and communicates with, first lumen 14. First lumen
14 and perfusion shaft 18 are adapted to receive a guide wire (not
shown). The guide wire enables directing catheter 10 to the
targeted arterial stenosis through manipulation at the catheter's
proximal end 19. Inflation shaft 20 outwardly extends from, and
communicates with, second lumen 16. First lumen 14 is adapted to
receive perfusion shaft 18, and second lumen 16 is adapted to
receive inflation shaft 20. In general, lumen 14 is between about
0.014 and 0.022 inches in diameter and lumen 16 is between about
0.010 and 0.016 inches in diameter, and preferably lumen 14 is
about 0.020 inches in diameter and lumen 16 is about 0.014 inches
in diameter. Generally, perfusion shaft 18 is between about 0.030
and 0.040 inches in diameter and inflation shaft 20 is between,
0.013 and 0.026 inches in diameter, and preferably shaft 18 is
about 0.039 inches in diameter and shaft 18 is about 0.018 inches
in diameter. It should be made clear, however, that the diameter of
perfusion shaft 18 may vary with a number of factors, for example a
patient's blood pressure.
As apparent to those skilled in the art, the length of catheter 10
and shafts 12, 18 and 20 will vary with arterial location and
patient characteristics. In one preferred embodiment of the
catheter as adapted for coronary treatment, catheter 10 is about
145 cm. in length, shaft 12 is about 135 cm. in length, and
perfusion shaft 18 is about 10 cm. in length.
Perfusion shaft 18 is circumscribed by inflatable balloon 22 and
extends beyond balloon 22 to perfusion shaft distal end 24.
Perfusion shaft 18 may extend between about 1 and 10 cm. beyond the
balloon to distal end 24, and preferably extends between about 2
and 4 cm. beyond balloon 22 to distal end 24. Inflation shaft 20
communicates with balloon 22 at inflation shaft distal end 26 and
at balloon proximal end 30, as clearly shown in FIG. 2.
Because inflation shaft 20 terminates at the balloon's proximal end
30, perfusion shaft 18 with circumscribing balloon 22 is of a
significantly smaller diameter than in prior systems where the
inflation shaft terminates further within the balloon, beyond the
balloon proximal end. As perfusion shaft 18 with circumscribing
balloon 22 is the largest diameter portion of catheter 10 that need
be inserted into an arterial stenosis opening, stenoses having
relatively narrow lumens may be successfully treated. Current
perfusion balloon angioplasty treatment of such narrow lumen
stenoses is not possible through use of conventional perfusion
balloon catheters that have too large a diameter to permit stenoric
insertion.
Inlet 32 communicates with second lumen 16 and thus in turn
inflation shaft 20. Fluid is introduced and discharged through
inlet 32 to inflate and deflate balloon 22.
Perfusion shaft 18 may extend from elongated shaft 12 to perfusion
shaft distal end 24 at least partially separate from and without
attachment to inflation shaft 20. In general, perfusion shaft 18
extends to perfusion shaft distal end 24 separate and without
attachment to inflation shaft 20 for at least about ten percent of
the length of perfusion shaft 18, and preferably perfusion shaft 18
extends from elongated shaft 12 separate from and without
attachment to inflation shaft 20, and then attaches to inflation
shaft 20 at inflation shaft distal end 26.
Perfusion shaft 18 has plurality of openings 34 extending
therethrough both proximal and distal to balloon 22. Openings 34
provide a path for blood flow through first carrier shaft 18 during
inflation of balloon 22. Blood perfuses through openings 34
proximate to balloon 22, flows through perfusion shaft 18, and then
flows out of catheter 10 through openings 34 distal to balloon 22
and through perfusion shaft distal end 24. By providing blood flow
through the artery during balloon inflation, long inflation times
at relatively lower inflation pressures can be employed affording
the noted advantages thereof.
Preferably, plurality of openings 34 circumscribe perfusion shaft
18 both proximal and distal to balloon 22. Each opening 34 may be
positioned relative to each adjacent opening 34 by a variety of
geometries. It is preferred, however, to radially offset each
opening 34 from each adjacent opening so that openings 34 spirally
circumscribe perfusion shaft 18, as shown in FIG. 3, and, most
preferably, each opening is radially offset from each adjacent
opening by a forty-five degree angle. Radially offsetting openings
34 has been found to provide particularly enhanced blood perfusion
into and through shaft 18.
The spiral circumscription of shaft 18 by openings 34 helps to
prevent problems encountered with previous catheters. In previous
catheters, the perfusion shaft openings, if present at all, are
typically positioned only on one side of the perfusion shaft. When
that shaft side contacts an arterial surface or is otherwise
obstructed, blood flow into the shaft will be blocked, preventing
blood perfusion through the artery during balloon inflation.
Circumscription of perfusion shaft 18 by openings 34 as in the
present invention ensures that even if blood flow is impeded to
portions of perfusion shaft 18, blood may freely flow through
openings positioned on other shaft portions.
It should be noted that circumscription of shaft 18 by openings 34,
and the advantages thereof, are preferably achieved by shafts 18
and 20 comprising two largely separate and unattached tubes. If the
two shafts were attached to comprise a single composite shaft, to
maintain the necessary separation of inflation fluid and blood,
either the perfusion openings could not circumscribe the composite
shaft or a much more cumbersome and less advantageous system than
the present invention would be required.
Distal end marker 40 is affixed to perfusion shaft 18 near
perfusion shaft distal end 24. Balloon marker 42 is affixed to
perfusion shaft 18 beneath balloon 22, preferably beneath the
center of the balloon. Proximal end marker 44 is affixed to
perfusion shaft 18 near perfusion shaft proximal end 38.
Markers 40, 42 and 44 are preferably composed of gold or platinum
or other radiopaque material and are attached to carrier shaft -8
by crimping. Markers 40, 42 and 44 are fluoroscopically visible and
aid in directing catheter 10 to, and centering balloon 22 in, the
diseased area of an artery.
Plurality of openings 34 preferably extend from perfusion shaft
proximal end 38 to balloon 22, and then from balloon 22 to distal
end marker 40. Openings 34 may be a variety of geometries in shape
and are preferably round. In general, openings 34 are between about
0.010 and 0.040 inches in diameter, preferably between about 0.014
and 0.024 inches in diameter, and most preferably about 0.022
inches in diameter. In general, the number of openings proximal to
balloon 22 may be about 4 to 40, preferably about 10 to 40, and
most preferably about 20 to 30. In general, the number of openings
distal to balloon 22 may be about 2 to 20, preferably about 4 to
10, and most preferably 6 to 8.
The dual-lumen shaft 12, perfusion shaft 18 and inflation shaft 20
are preferably formed separately through a polymer extrusion
process. In one preferred embodiment, first lumen 14 is attached to
perfusion shaft 18, and second lumen 16 is attached to inflation
shaft 20, by means of a suitable adhesive or heat bonding. Balloon
22 is attached to perfusion shaft 18 by an adhesive or heat
bonding. Plurality of openings 34 are cut or drilled through
perfusion shaft 18. Heat bonding is the preferred means of
attaching inflation shaft distal end 26 to shaft 18.
As with previous catheters, the catheter of the present invention
is inserted into a patient and advanced to the area of treatment by
means of the guide wire and markers 40, 42 and 44. Prior to
insertion into the patient or to positioning within the lesion
lumen, balloon 22 is prepared for use by introducing a pressurized
fluid through inlet 32 thereby displacing trapped air from balloon
22, inflation shaft 20 and second lumen 16. A negative pressure is
then applied to withdraw the fluid and deflate the balloon.
Thereafter, balloon 22 is inflated and deflated as desired.
The foregoing description of the present invention is merely
illustrative thereof, and it is understood that variations and
modifications can be effected without departing from the spirit or
scope of the invention as set forth in the following claims.
* * * * *